A popular New Canaan 10-year-old is the first child in Connecticut to die of flu-related illness this season — a brutal blow to those who knew him and another shocking casualty of a devastating flu season.

“It was like being hit on the head. I couldn’t believe it,” said Tomasz Piateck, who coached the late Nico Mallozzi on the RoughRiders 2007s hockey team. “No family should have to deal with something like this.”

Mallozzi’s death Sunday — officially from complications linked to influenza type B — “serves as a reminder of how bad the flu can be,” said Dr. Richard Martinello, director of infection prevention at Yale New Haven Hospital.

Mallozzi fell ill shortly before his hockey team, the RoughRiders, were to compete in a tournament in upstate New York over the weekend.

“Nico was not feeling well but wanted to go to Buffalo with his team,” said Dr. David Reed, New Canaan director of health.

During the tournament, in which he didn’t compete, Mallozzi felt so sick his parents took him home. Along the way, he took a turn for the worse and was rushed to the Women & Children’s Hospital of Buffalo.

His family tried to return home Sunday, but only made it as far as the Catskills region before Mallozzi took another bad turn, and was brought to a New York hospital, where he eventually died.

His brother Joey, 12, has also tested positive for influenza B, and been hospitalized. Monday night, a GoFundMe page was created for the “Nico Mallozzi Memorial Fund” and had nearly reached its goal of raising $100,000 by 6 p.m. Tuesday.

“There are no words to describe the loss we feel,” said a statement from the Mallozzi family on the GoFundMe page. “But we are so appreciative and grateful for the outpouring of support from so many in our hockey family and local community.”

Terrible season​The flu is a contagious respiratory illness that can be deadly, but it’s typically most damaging in those younger than 5 and older than 65, which is what makes Nico Mallozzi’s case so puzzling.

“It’s definitely unusual to see (a death) in a 10-year-old,” Martinello said.

Nationwide, 20 children had died from flu-associated deaths as of Jan. 6, according to the Centers for Disease Control and Prevention. This time last season, only three children had died from the illness.

The steep increase in flu-associated pediatric deaths is part of what is turning out to be a terrible season for the disease. Flu fears began early last year when the Southern Hemisphere got its flu season, which typically begins in April. Australia in particular was hit hard, having its most severe flu season since 2009.

Once the Northern Hemisphere’s season began in mid-fall, fears were high the illness would be rampant here as well.

In Connecticut, the Department of Public Health reported that, as of Jan. 6 — the most recent date for which numbers were available — roughly 1,015 people had tested positive for the flu and 456 had been hospitalized with flu-related illness.

Compare that to the same point of last season when, according to past reports from the state, 614 people had tested positive for flu and 270 had been hospitalized.

The strain circulating most widely on both sides of the globe has been type A influenza, which makes it somewhat unusual that Mallozzi and his brother contracted type B.

“Influenza B is not the predominant strain,” Martinello said. “But, as we know, multiple strains of flu circulate throughout the season.”

The CDC reports that only about 17 percent of those testing positive for flu have had influenza B. A CDC spokesperson said the effectiveness for this year’s vaccine hasn’t yet been determined but, typically, vaccines are roughly 50 percent effective against B viruses.

For years, it was thought that illness caused by influenza B viruses was less severe than sickness caused by influenza A, but a CDC study released in 2014 debunked that.

The study looked at disease characteristics, including severity of illness, associated with both types of flu in hospitalized patients over eight flu seasons — the 2005-2006 season through the 2012-2013 season.

Researchers found no significant difference in the proportion of hospitalization by virus type for each season, and both types lead to a similar proportion of deaths.

’Always happy’

In the days following Nico Mallozzi’s death, the New Canaan community mourned the loss of a child possessed of seemingly boundless energy.

“I could spend hours talking about what kind of kid he was,” Piateck said. “He was quite a character — always smiling, always happy, always on the rink and running around with the other kids.”

Piateck said Mallozzi, who was the third of four children, joined the hockey team four years ago at the age of 6, after watching his older brother play in the organization’s upper divisions.

“He was a strong kid, a great athlete, and whatever position I needed him to be, he would play,” Piatek said. “Whenever I needed him, he was there.”

On Tuesday, the RoughRiders Hockey Club announced that, effective immediately, the club would be taking special precautions because of an increase in flu cases statewide. Players are asked not to share water bottles, to keep their gloves on during handshake lines and to skip practice if they’re experiencing flu symptoms.

Reed said the New York medical examiner’s office determined that Mallozzi’s flu, complicated by pneumonia, led to sepsis, which was the cause of death.

That’s not uncommon, Martinello said. “The (flu) virus infects the respiratory tract, including the lungs, which can lead to pneumonia,” he said.

Influenza is a particularly common cause of pneumonia in young children, the elderly, pregnant women and those with chronic health conditions, according to the American Lung Association. Most flu cases don’t lead to pneumonia, but those that do tend to be more severe.

Meanwhile, Piateck said Mallozzi’s’ absence will be felt by every member of the team and their families.

“Our team will never be the same,” he said. “We still can’t believe this is happening. It’s going to be hard for everyone to not see Nico out on the ice. So, we’re just going to take it day by day and we’re going to try to be strong for him.”

​Fast flu facts• Some basic statistics on flu-related deaths in children• Since 2004-2005, flu-related deaths in children reported to CDC during regular flu seasons have ranged from 37 to 171.• As of Jan. 6, there were 20 flu-associated deaths nationwide of children during the current flu season.• 14 of those children had influenza A and six had influenza B.• Last flu season at this point, only three children had died from flu.